FIG. 1 shows the current method of video distribution. Video signals are processed by a MPEG (moving pictures expert group) multiplexer 110 and fed to an edge QAM (quadrature amplitude modulator/demodulator for switched digital video). The multiplexer and edge QAM 120 are often combined into the same device which produces RF (radio frequency) output which is then combined (as an analog signal) in a combining network 130 which is then modulated onto a laser 140, carried over a fiber optic network, and converted back to an RF signal at the edge 150. This is known as a hybrid fiber/coax network.
As the bandwidth of the signal carried across the laser increases, the signal quality decreases. Eventually, gains in capacity that were previously achieved by making the bandwidth larger are lost to decreased signal quality. To continue increasing bandwidth capacity to the edge of the network, a different approach is needed.